(1) Field of the Invention
The present invention relates to a diacetylene compound having at least one double bond, which has excellent curing reactivity and provides a shaped article having a high elastic modulus, and to a shaped article thereof.
(2) Description of the Related Art
As the thermosetting resin, a phenolic resin, an epoxy resin, an unsaturated polyester resin and other resin are known. However, cured shaped articles obtained from these resins have an elastic modulus of 4 to 5 GPa at highest. Therefore, when these resins are utilized as materials having high strength and high elastic modulus, they are used as fiber-reinforced composite materials.
Recently, an imide material having an ethynyl group or a mixed material comprising an imide compound having a diacetylene bond at the terminal and a dienophile compound has been investigated as a new curing material, and possibilities of this new curing resin have been examined (see U.S. Pat. Nos. 4,311,601, 4,402,879 and 4,405,786). However, the elastic modulus of a cured shaped article of this curing resin is not superior to that of a cured shaped article of a conventional curing resin.
Separately, a fiber having a high elastic modulus has been manufactured on an industrial scale by highly orienting a non-curable linear polymer. For example, there can be mentioned a gel-spun fibrous product of polyethylene and a liquid crystal-spun fibrous product of poly-p-phenylene terephthalamide.
In these materials, however, a high elastic modulus is manifested in the orientation direction but the elastic modulus is low in the direction rectangular to the orientation direction.
As an interesting example, there can be mentioned an investigation in which a whisker polymer close to a single crystal is synthesized by solid-phase reaction of a diacetylene compound having urethane bonds, sulfonyl bonds or other bonds [see Polymer, 24, 1023 (1983); Journal of Polymer Science, Polymer Physics Ed. 17, 569 (1979); and Report 1984 (Order No. AD-A140912)]. However, as in case of the above-mentioned highly oriented linear polymer, a high elastic modulus can be manifested only in one direction and it is impossible to manifest high strength and elastic modulus two-dimensionally or three-dimensionally.